CVE-2026-72529Known exploitationNetwork attack vector

Unauthenticated script execution via undocumented function

Published Aug 19, 2026 · Updated Aug 21, 2026

Missing authentication in TrueConf Server 5.3.x before 5.3.9, 5.4.x before 5.4.9, and 5.5.x before 5.5.5 allows remote attackers to run scripts over 4307/TCP. The service on 4307/TCP exposes an undocumented critical function without authentication and forwards attacker-supplied script content into the server's isolated execution environment; Kaspersky reported earlier releases since 2022 were also vulnerable. No credentials or user interaction are required, but direct host-level command execution depends on chaining the separate sandbox-escape issue CVE-2026-72530.

CVSS severity9.8
Critical
EPSS probability1.55%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authentication in TrueConf Server 5.3.x before 5.3.9, 5.4.x before 5.4.9, and 5.5.x before 5.5.5 allows remote attackers to run scripts over 4307/TCP. The service on 4307/TCP exposes an undocumented critical function without authentication and forwards attacker-supplied script content into the server's isolated execution environment; Kaspersky reported earlier releases since 2022 were also vulnerable. No credentials or user interaction are required, but direct host-level command execution depends on chaining the separate sandbox-escape issue CVE-2026-72530.

The record

CVE
CVE-2026-72529
Published
Aug 19, 2026
Updated
Aug 21, 2026
Vendor
TrueConf
Product
TrueConf Server
Classifications
CWE-306, T1210
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=* <5.3
  2. Affected versionversion=5.3 <5.3.9
  3. Affected versionversion=5.4 <5.4.9
  4. Affected versionversion=5.5 <5.5.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

TrueConf · TrueConf Serverversion=* <5.3; version=5.3 <5.3.9; version=5.4 <5.4.9; version=5.5 <5.5.5

Published CVSS scores

9.3Kaspersky CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8TrueConfCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

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Your stack

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